New Williston wind tunnel leads industry

SOH Wind Engineering owner Svend Ole Hansen (left) shows the 125-horsepower fan at the end of the Williston company’s wind tunnel to Gov. Peter Shumlin Monday. The fan can create winds up to 65 miles per hour. (Observer photo by Stephanie Choate)

By Stephanie Choate

Observer staff

A wind industry giant has begun blowing in Williston.

Monday marked the grand opening of the world’s largest calibration wind tunnels, housed in a nondescript industrial building on Leroy Road.

Massive fans at the end of two 125-foot long tunnels, 10 feet wide and 10 feet tall, mimic natural wind conditions, testing the effect of wind on large structures like bridges, buildings and offshore drilling platforms. The Williston wind tunnels also test the accuracy of wind sensors, known as anemometers, used to measure wind speed.

Hinesburg-based renewable energy company NRG Systems provides the bulk of the wind tunnels’ business, sending approximately 100 anemometers to be tested each day.

Bigger is better when it comes to accurate calibration, Hansen said. SOH can build larger models on which to test the wind’s effects, and there is more space between the item being tested and the walls, meaning less interference. Most calibration wind tunnels in the industry are roughly 3 by 3 feet.

“The large size is very important in order to have an accurate reading,” Hansen said, standing next to an anemometer spinning lazily in the 5 mph breeze.

As Hansen led the tour into the adjacent wind tunnel, a seemingly small increase in wind speed to 15 mph revealed a steadily whirling anemometer—disheveling hair and sending ties flapping in the process.

“This is our first in Vermont, so it’s a big deal,” Shumlin said of the tunnel.

Aside from providing jobs and the opportunity to train students in cutting edge technology, the wind tunnels help address one of the “the biggest challenges we face as a state and as a species … climate change,” he said.

SOH decided on Williston because of its close working partnership with NRG Systems and its proximity to the University of Vermont, Hansen said.

Two mechanical engineering students from UVM are currently working at SOH. Aside from the students, five people are employed at the Williston facility, and the company expects to hire two to three more employees this year.

Before the Williston tunnels opened, NRG sent its anemometers to be calibrated in a lab in California and SOH’s sister company in Copenhagen.

When owners of the lab in California told NRG of its impending closure, NRG sent out a request for a facility that could take over the calibration work. Hansen decided to build a facility in Vermont, funded in part by a $150,000 grant under the Vermont Economic Growth Initiative.

Using the Williston facility will save NRG $600,000 to $700,000 annually, said NRG Purchasing Manager John Kerr.

Sending the technology over one town, rather than across the county or the Atlantic Ocean, also reduces NRG’s environmental impact, which NRG CEO John Norton said is part of the company’s mission.

“We’re very excited to be a part of this celebration,” Norton said at the grand opening Monday. “Svend is a recognized leader in wind energy.”

SOH Wind Engineering currently works with a total of four companies—though general manager Rob Stewart said demand increases by the week.

Currently, the wind tunnels run 18 hours a day during the week and 12 hours on the weekends. They calibrate approximately 100 anemometers per day. Each one must be tested individually, which takes about 20 minutes.

Stewart said the facility has the capacity to run 24 hours a day as demand increases.

It took SOH Wind Engineering approximately one year to turn on the wind in the first two tunnels. The company expects to complete two more wind tunnels next winter. The inner walls of the four tunnels will be removable, allowing for one massive wind tunnel.